I. Field of the Invention
The present invention relates generally to vehicles having an electrically operated load device, and more particularly, to such a device employing a photovoltaic cell for charging the electrical power source or operating the load device.
II. Description of the Prior Art
There are many previously known forms of motorized vehicles. In particular, it has also been previously known to provide a motor means for driving a bicycle in order to supplement or replace the manually driven pedal mechanism provided on such vehicles. Although such bicycles are often powered by a small internal combustion engines, it has also been known to employ electric motors powered by a battery source. Such battery powered units are substantially quieter than the internal combustion engines, and can be substantially less expensive to operate.
However, the disadvantage of battery powered propulsion units is that the battery discharges and must then be recharged or replaced. Since replacement of the battery is relatively expensive, it is preferable to recharge the battery. Quite often, the recharging unit is a stationary device which can be connected to the battery on the bicycle when the bicycle is not in use. Although some battery chargers are portable, such units are still quite bulky and, therefore, not readily transported on a vehicle such as a bicycle. Consequently, the range of travel of such a vehicle is limited. Furthermore, chargers are typically operated by plugging into a standard AC outlet, and thus, as a practical matter, are immobilized when operative. Consequently, the vehicle is unavailable for use during recharging of the battery unless the battery is removed and replaced by a fully charged battery.